Foetal Development and Placental Health in Response to Apical Periodontitis Induced in Pregnant Wistar Rats

AIM: This study investigates the relationship between maternal apical periodontitis (AP) and neonatal health. METHODOLOGY: Twenty-four Wistar rats were assigned to three groups: control (CN), one induced apical periodontitis (AP1), and four induced apical periodontitis (AP4). Apical periodontitis was induced for all experimental groups. After 30 days, the rats were mated and sacrificed on the 21st day of gestation. Placental weight, maternal glycemia, insulinemia, insulin resistance, and placental protein levels were analysed. Neonates were evaluated for their number, weight, capillary glycemia, and liver tumour necrosis factor-α (TNF-α) content. RESULTS: The results showed that no significant differences were observed in maternal glycemia. However, insulinemia and homeostatic model assessment for insulin resistance were higher in the AP groups compared with CN and were more pronounced in AP4 than AP1. Placental weight and placental labyrinth area were reduced exclusively in the AP4 group, while the number of fetuses per rat did not differ among groups. The AP4 group exhibited increased placental TNF-α gene expression and protein content compared with CN and AP1. In addition, placental caspase-3 expression was increased in the AP4 group, with no significant differences in nuclear factor-kappaB (p50 and p65) phosphorylation status among groups. Foetal analyses demonstrated a reduction in naso-anal length in fetuses from the AP4 group, lower capillary glycemia in fetuses from AP rats compared with CN, and increased TNF-α content in foetal liver tissue from AP groups. CONCLUSIONS: Overall, most alterations were more pronounced with an increasing number of maternal teeth affected by AP, emphasizing the importance of maternal oral health in preventing placental dysfunction and adverse fetal developmental outcomes.